$\text{}^{13}$C High Resolution NMR Study of Methyl-Diethyl Sulfonium TCNQ 1:2 Complex

Solid state high resolution $\text{}^{13}$C NMR studies of a 1 : 2 charge transfer complex of TCNQ with diethyl-methyl sulfonium S + Et$\text{}_{2}$Me(TCNQ)$\text{}_{2}$ are presented. The metallic shifts of TCNQ resonances are interpreted as due to the Pauli paramagnetism of conducting electrons and quantitatively connected with inhomogeneous spin density distribution over (TCNQ2)¯ dimer. A singularity of NMR parameters at T = 330 K is observed and described as a structural phase transition occurring in the S + Et$\text{}_{2}$Me cation sublattice.